Self-aligned ZnO nanoparticle-based TFTs for flexible electronics

In this study, we present an integration routine for self-aligned ZnO nanoparticle-based thin-film transistors (TFTs) to be implemented on flexible electronics. As a proof of concept, first experiments were performed on a borosilicate glass, and subsequently the integration process was carried out on a polyethylene terephthalate (PET) substrate. The TFTs operate at low voltage (VON around 1 V) and depict ION/IOFF in the range of 105, field-effect mobility of about 1-2 cm(2)V(-1)s(-1) and subthreshold swing of about 0.6 V/dec. Aiming at a later high throughput process, spray-coating technique was employed for the deposition of the aqueous dispersion containing the ZnO nanoparticles. Moreover, a nanocomposite was used as high-k gate dielectric. In addition to the self-alignment process for the gate electrode, which drastically decreases gate parasitic capacitances, a similar method is also discussed for the patterning of the active semiconducting layer for the reduction of cross-talk effect.